Eigen Increment Column by One - c++

Question

How to increment a column of a dynamic matrix by one, as an in place operation (without creating copies/intermediates) ?
Attempt:
#include <Eigen/Dense>
#include <iostream>
#include <stdint.h>
int main(void){
Eigen::MatrixXf A;
A = Eigen::MatrixXf::Random(3, 5);
std::cout << A << std::endl << std::endl;
A.col(1) = A.col(1)*2; //this works.
A.col(1) = A.col(1) + 1; //this doesn't work.
std::cout << A << std::endl;
}

Answer 1

I found a way to do this. But I don't know if the operation is in place.
This is similar to eigen: Subtracting a scalar from a vector
#include <Eigen/Dense>
#include <iostream>
int main(void){
Eigen::MatrixXf A;
A = Eigen::MatrixXf::Random(3, 5);
std::cout << A << std::endl << std::endl;
A.col(1) = A.col(1)*2;
A.col(1) = A.col(1) + Eigen::VectorXf::Ones(3);
std::cout << A << std::endl;
}
Another way is to use array operation. This way seem better (I guess).
https://eigen.tuxfamily.org/dox/group__TutorialArrayClass.html
#include <Eigen/Dense>
#include <iostream>
int main(void){
Eigen::MatrixXf A;
A = Eigen::MatrixXf::Random(3, 5);
std::cout << A << std::endl << std::endl;
A.array() += 1;
A.col(1).array() += 100;
std::cout << A << std::endl;
}